How to see all the tables in an HSQLDB database?

2009-02-27 sql hsqldb

I usually use SQLDeveloper to browse the database, but I couldn't make it work with HSQLDB and I don't know which tables are already created… I guess it's a vendor-specific question and not plain SQL, but the point is: how can I see the tables so I can drop/alter them?

Answers

The ANSI SQL92 standard for querying database metadata is contained within the INFORMATION_SCHEMA data structures.

I have no idea whether your database supports this or not, but try the following:

SELECT *
FROM   INFORMATION_SCHEMA.TABLES

On further research, it appears that HSQLDB does support INFORMATION_SCHEMA, but with slightly non-standard naming.

All of the tables have SYSTEM_* prepended to them, so the above example would read

SELECT *
FROM   INFORMATION_SCHEMA.SYSTEM_TABLES

I have no means of testing this, and the answer was found on sourceforge.

Check out DBVisualiser and SQuirreL SQL Client. Both of these have support for HSQLDB, and a GUI for editing/modifying/viewing the tables.

Awesome, thanks! Been scouring the Web for that info. This will fetch only your tables' field info:

SELECT TABLE_NAME, COLUMN_NAME, TYPE_NAME, COLUMN_SIZE, DECIMAL_DIGITS, IS_NULLABLE FROM INFORMATION_SCHEMA.SYSTEM_COLUMNS WHERE TABLE_NAME NOT LIKE 'SYSTEM_%'

You can retrieve indexes, primary key info, all kinds of stuff from INFORMATION_SCHEMA.SYSTEM_TABLES. Gotta love oo documentation :p

You run querying using hsql database manager, are you? If you use this, below may give some hints:

Select your connection:

  1. type: HSQL DATABASE ENGINE SERVER
  2. Driver: jdbc.hsqldb.jdbcDriver
  3. URL: jdbc:hsqldb:hsql://localhost/

Then, you will browse the database.

If you're on the command line, you may want to try the Hsqldb SqlTool, documented in the SqlTool Manual (hsqldb.org).

  • Put your database connection information in "~/sqltool.rc" and choose any DBNAME you want, substitute correct username and password, if known.
    • urlid DBNAME
    • url jdbc:hsqldb:/path/to/hsql/database
    • username SA
    • password
  • Install tool with: apt-get install hsqldb-utils (on Ubuntu)
  • Connect with hsqldb-sqltool DBNAME # on Ubuntu
  • Hint for other systems: java -jar YourHsqlJar.jar DBNAME
  • Show tables with: \dt
  • Show columns with: \d TABLENAME
  • Standard queries like: SELECT * FROM …;
  • Edit (append) last command with: :a
  • Quit with: \q
  • View special commands with: \? OR :?

Good luck!

Use the \dt command when you hit the >sql prompt in the command line for HSQLDB.

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